If you're referring to what agencies, it would depend on what "part" of Cypress you're in.
If you're closer to the FM 529/Fry area, you'd want to monitor HCSO 4 (Harris county sheriff's district 4), C5 disp1 (Harris county constables precinct 5), Cyfair VFD and maybe DPS Houston 1 or HCSO 5 (district 5 starts at FM 529 and Barker Cypress, extending northeast from there)
If you're on the other side of 290 but still close to 290, you'd want HCSO 5, C4 disp1, Cyfair VFD and maybe DPS Houston 1 or HCSO 4.
If you're closer to 249, I'd monitor HCSO 5, C4 disp1, HCSO 1 (east of 249 as district 5 ends at 249) and CyCreek EMS (though recently I heard they're now an ESD).
I know I'm forgetting a FD or five (Rosehill if you're closer to Waller I believe and another one I can't recall).
For HCSO sometimes the back channels and odd channels are where it's at. HCSO 4 you'll have SW and TAC4. HCSO 5 would be West (I've seen/heard it called northwest as well) and TAC5. Hot Spots and HCSO disp6 can be (used to be) good if they're doing any sort of focused enforcement but I don't see them used as often as they prefer to work off the gulf coast taskforce channels (or whatever they're called) to maintain convert.
Hope this helps a little. Not on here often but monitor Harris county everyday.